Most living things need oxygen to survive. Oxygen helps organisms grow, reproduce, and turn food into energy. Humans get the oxygen they need by breathing through their nose and mouth into their lungs. Oxygen gives our cells the ability to break down food in order to get the energy we need to survive.
- All cells in our body need oxygen to create energy efficiently.
- When the cells create energy, however, they make carbon dioxide.
- We get oxygen by breathing in fresh air, and we remove carbon dioxide from the body by breathing out stale air